Nigerian Ambrose, 24, and Wilson, 27, played in Celtic's 3-0 defeat to Juventus in the Champions League last 16, with the former receiving considerable flak following a poor performance that saw him make vital mistakes in defence and attack, just a few days after he had helped Nigeria win the African Cup of Nations.

Speaking to The Scotsman, Lennon said: "Efe is strong-minded regarding the criticism. He is very humble and was extremely disappointed after last Tuesday night.

"Overall, he has been brilliant for us and there has been a lot of interest in him. Not just in England, but from the continent as well.

"I don't think we will lose him in the summer as he is just in the door and there is more he can add to his game. But he has a few admirers out there with his performances this season.

"Efe has been a great signing for us. He has also brought the best out of Kelvin Wilson, who has been magnificent this season. At European level, they have made us better."

Wilson's emergence is in stark contrast to last season, which saw the defender struggle with injuries and personal problems following his free transfer from Nottingham Forest.

So marked is his improvement that he has caught the eye of Roy Hodgson, who was in attendance for Celtic's game with Juventus to take in Gary Hooper's performance.

Lennon continued: "Roy was very complimentary about Kelvin after seeing him against Juve.

"I think Kelvin is worth looking at. He is a modern-day centre-half, who is composed on the ball.

"Kelvin had a few things in his private life which unsettled him when he first came here. I also don’t think he realised how big the club was and the pressure that came with it.

"He has improved aspects of his game, like his heading, and he has become dominant. He also has pace, which is a huge asset."